Added proper "need 'this' to access member foo" errors instead of "variable foo not resolved" for some cases, added FIXME for the old error! Added a bit more information to the runtime's cyclic dependency detection exception.

module bug4;

int func(int i)
{
    i += 2;
    i -= 3;
    return i;
}

void main()
{
    assert(func(4) == 3);
}